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MongoDB Many-to-Many Association
...ractical level, the release of Couchbase 4.0 has meant that, for the first time, you can do native JOINs in NoSQL. They use their own N1QL. This is an example of a JOIN from their tutorials:
SELECT usr.personal_details, orders
FROM users_with_orders usr
USE KEYS "Elinor_333137...
Add file extension to files with bash
... this elegant and simple solution -- I have landed on this answer multiple times, but can't seem to memorize it. #dejavu
– Tim Andersen
Jan 30 '19 at 18:11
add a comment
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Splitting on last delimiter in Python string?
....rsplit(',', 1)
s.rpartition(',')
str.rsplit() lets you specify how many times to split, while str.rpartition() only splits once but always returns a fixed number of elements (prefix, delimiter & postfix) and is faster for the single split case.
Demo:
>>> s = "a,b,c,d"
>>> ...
How can I comment a single line in XML?
...the bottom comment. The downside is having to edit the bottom comment each time, which would probably make it easier to just type in <!-- at the top and --> at the bottom each time.
I also want to mention that other commenters recommend using an XML editor that allows you to right-click and c...
Is it possible to program iPhone in C++
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Objective-C and C++ came about at around the same time, both with the goal of adding object oriented programming to C. Objective-C followed Smalltalk’s model of everything being dynamic dispatch, C++ chose to use function pointers (virtual methods) basically. The weird sy...
Common elements in two lists
... Contains looks like it'd be an O(n) operation, which would be called n times, unless the compiler does something clever. Does anyone know whether the above runs in linear or quadratic time?
– Regorsmitz
Aug 12 '16 at 20:56
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In log4j, does checking isDebugEnabled before logging improve performance?
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String.format is 40 times slower than concat & slf4j has limitation of 2 params See numbers here: stackoverflow.com/questions/925423/… I have seen many a profiler graph where the format operation is wasted in debug statements when the p...
Hand Coded GUI Versus Qt Designer GUI [closed]
...em by hand if you really wanted to) can often be dynamically loaded at run-time (Qt and GTK+ both provide this feature). This means that you can make layout changes and test them without recompiling.
Ultimately, I think both raw code and UI tools can be effective. It probably depends a lot on the ...
Replace whitespaces with tabs in linux
...ere're many ways to do something. If you plan to do this substitution many times you will search a solution with a good performance, but if you are going to do it only once, you will serach for a solution wich involves a command that make you feel confortable.
– Jonathan
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Why is volatile needed in C?
...laying with data that isn't concurrency protected. And yes there are valid times to be doing that, you can for example write a thread safe circular message queue without needing explicit concurrency protection, but it will need volatiles.
– Gordon Wrigley
Oct 2...